Technology : The video that knows where it lives

时间：2019-02-27 03:19:01166网络整理admin

By Barry Fox NEXT month a video recorder comes on the market that should soon be helping the police with their inquiries. When the Sharp video recorder is first used, owners enter their postcode and a personal identification number (PIN) via the remote control. Whenever the machine is used subsequently, it briefly displays the code on screen. This will be a boon for police trying to trace the owner of recorders found in the possession of a thief or someone dealing in stolen goods. Simply connecting the video to a television will reveal where it has come from. It will also act as a warning to prospective buyers that the machine has been stolen. Both post and PIN codes are stored in a EPROM chip, a special kind of reprogrammable memory chip, similar to those used to store the channel settings. The chip remembers the codes even when the machine is disconnected from the power supply. The video can be retuned at any time but the postcode can only be changed by a user knowing the PIN. This way, the rightful owners will be able to change the postcode if they move house or sell the video, but burglars and anyone who has bought a stolen video will not. Removing the EPROM is no help, because it stops the video recorder working altogether. Previous anti-theft schemes for video machines have required users to enter a PIN before the machine will work. But this has never been popular. Owners find it inconvenient to enter a number every time they want to use the recorder. They either forget their PIN or write it down near the video,